


The Universe Is Change

by Mara



Category: S.C.I.谜案集 | S.C.I. Mystery (TV)
Genre: Alternate Universe - Soulmates, Episode Related, M/M, Soulmate-Identifying Marks
Language: English
Status: Completed
Published: 2020-06-21
Updated: 2020-06-21
Packaged: 2021-03-04 04:35:07
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,957
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24843919
Author URL: https://archiveofourown.org/users/Mara/pseuds/Mara
Summary: To begin with, Bai Yutong would like it noted that the entire concept of soulmates and soulmarks isridiculous.
Relationships: Bái Yùtáng/Zhǎn Zhāo
Comments: 12
Kudos: 146





	The Universe Is Change

**Author's Note:**

  * For [UndeadRobins](https://archiveofourown.org/users/UndeadRobins/gifts).



> I always have to twist tropes just a bit, because I’m ornery like that. Also, I’ve stolen some bits of dialogue from ep. 24, but I’ve adjusted them to fit my needs.

To begin with, Bai Yutong would like it noted that the entire concept of soulmates and soulmarks is _ridiculous_. Yeah, some people discover that they have these…weird shapes on their skin and they match someone else’s weird marks and then they date each other. But it’s clearly like the fucking Rorschach test and people just find matching marks with someone they’re interested in.

Which is why when Qingtang pointed out that he and Zhan Yao both had a little heart shape on their shoulder, he rolled his eyes and asked “Yeah, so what?”

Zhan Yao echoed the sentiment.

(They were 14 years old at the time. That was the height of their eloquence.)

* * *

As they got older, Yutong very carefully never looked at the mark on his shoulder, nor did he look at Zhan Yao’s shoulder. Because his Cat was _not_ his soulmate or some crap like that, he was a sometimes annoying guy he hung out with because their families were close.

Well, yeah, they were friends. But that was it.

He absolutely never did any research about soulmates or soulmarks but sometimes coworkers or dates or random people would gush about the topic, so he learned way more than he wanted to about the shit people believed.

“The marks can change,” the baby gay who was chatting him up in the bar said. “If you don’t accept your soulmate or if one of you changes too much.”

“If a mole on your skin changes, you should go see a dermatologist,” Yutong said, taking a sip of his whiskey and trying to not roll his eyes.

The baby gay frowned (prettily, though). “You don’t believe in soulmates?”

“Nope.” He took another sip of whiskey. “Romantic but impractical. How does it even _work?_ ”

That guy went home with someone else and Yutong shrugged as he finished his drink. He wasn’t so desperate that he’d say things he didn’t believe just to get laid.

Zhan Yao chuckled when Yutong told him the story later over the phone. “If you didn’t want to have sex with him, there were other ways to turn him down.”

“Ugh, why do I even talk to you?”

“Because you’re at the police academy and you don’t want to reveal you’re gay.”

Yutong sighed. “Just for that, I’m going to find another gay guy here so I have someone to talk to.”

“That’s childish.”

“That’s what you always say to me.”

“Because you’re always childish.” Zhan Yao’s smirk was actually _audible_ and how did that work?

“Whatever. Good night.”

“Good night, Mouse.”

Yutong put down the phone and stared at the ceiling. Qingtang was out of her mind if she thought that man was his soulmate.

* * *

Yutong graduated, joined the police force, worked his way quickly up the ranks by dint of being very good at his job. Li Jiankang, his first partner in homicide, claimed to have found his soulmate by their matching soulmarks on the inside of their wrists. If you squinted, it sorta kinda looked like a diamond, Yutong supposed.

At least by this point in his life he’d learned enough tact to not piss off his partner and he smiled and said “Congratulations” instead of lecturing him about confirmation bias and other psychological stuff he’d somehow picked up from talking to Zhan Yao.

For two years they solved a lot of boring and depressing murders. And then they solved a much less boring murder: A supposed soulmate killed his wife of 10 years.

Friends, neighbors, coworkers, everyone talked about how happy they’d been to have found their soulmate and how impossible it was for him to be the murderer. It seemed like everyone who lived in a 10-kilometer radius had been shown their matching marks, which looked like a lotus root.

Yutong bit his tongue as Jiankang insisted they consider other possible suspects and went along with it. Until his phone rang.

“Bai Yutong,” barked the medical examiner. “What are you doing?”

“Sir?” Yutong shot his partner a startled glance.

“Are you sending me the wrong body?”

“No, sir. Absolutely not.” 

“Then where is the deceased’s soulmark supposed to be?” the medical examiner said with clearly exhausted patience.

“Where is her soulmark?” Yutong repeated, gesturing at Jiankang, who mouthed ‘back of the neck’. “On the back of her neck.”

“I’m looking at her neck right now and I don’t see anything like what you’ve described. Find out what the hell’s going on.”

It took them half an hour to track down the husband, who was with his parents. Yutong followed his partner in, hanging back as Jiankang politely asked to speak with the husband privately.

“What’s wrong?” the husband said, looking between them. “Have you caught the murderer?”

“We need to see your soulmark,” Yutong said when it looked like Jiankang was going to waffle.

With a frown, the man looked between the two of them. “Pardon me?”

“You’ve shown it all around town, so we’d like to see it as well.” Yutong ignored his partner’s obvious discomfort, facing down the suspect with a firm look.

“I’m sorry, but I don’t think you need to do that.” 

“You can show it to us now or we can all go back to the station. Your choice.” This was incredibly suspicious, so much so that even Jiankang was starting to look at the man in front of them and scowl.

The suspect glared, but bent his head, brushing aside his hair. Yutong could see two random moles but definitely nothing like had been described to him as a lotus root. He looked at Jiankang, who looked shocked.

“Sir, you’ll have to come with us…”

* * *

“This is exactly what I mean,” Yutong complained to Zhan Yao, who just sighed. “Everyone went on about how they’re soulmates and he’s the one who killed her.”

“They no longer had their soulmarks, which does seem to be evidence for the theory that they can change and even disappear under some circumstances.” Zhan Yao sounded like he was typing on his end of the phone line.

“That makes no sense!” Yutong swung his feet up on his desk and glared balefully at them. “How can you be someone’s soulmate and then not?”

“People change.”

That phrase sat heavily on both of them for a long moment. “Why would this…magical thing that supposedly knows your perfect match just disappear?”

“That—”

“It’s all bullshit, just like I’ve been saying all along.”

“But—”

“How do you change enough to _kill_ someone you supposedly love?”

Pause. “Are you done?”

“Yeah.” Yutong scowled harder at his shoes and the scuff he was going to have to polish out.

“The question of soulmarks and soulmates is complicated. What research has been done shows that people in a relationship with their soulmate are happier than those with a non-soulmate.”

“So they think they’re—"

“Bai Yutong!”

“Sorry,” he muttered.

“There are many unknowns, however. Perhaps you’re correct and they believe they’re going to be happier, so they are. Perhaps people not with a soulmate doom themselves to an unhappier relationship. But how do you test that, exactly? We can’t randomly divide people into groups, for one thing.” Zhan Yao sighed. “I know you don’t believe in it, but most people do. Whether you believe or not, you have to accept that.”

“Fine. I do.”

“But do you understand _why_?”

Yutong leaned his head back and stared at the ceiling. “People want certainty,” he said eventually. “Someone or something to tell them they’re doing the right thing.”

“That’s part of it, yes.”

“They want to believe in happily ever after.”

“Mmm. Yes, I suppose.” Zhan Yao was drumming his fingers on a table. “It’s a powerful romantic vision, the idea of the person who’s most perfect for you in the entire world. Its truth is, to an extent, irrelevant. People believe because they want that perfect love to be real.”

“I don’t like it.”

The smile was plain in Zhan Yao’s voice. “I had a suspicion.”

Zhan Yao had work to do and Yutong was exhausted and ready to head home. They made their goodbyes and Yutong grabbed his jacket and left the office he shared with Jiangkang, waving a farewell to other officers still working. One murder solved, but there would surely be more tomorrow.

* * *

Zhan Yao went to America, Li Jiangkang moved to Taiwan, and Bai Yutong moved up the ranks again. Qingtang bought him a flashy car, which he complained about but not-so-secretly loved. 

Time zones and jobs and personalities meant that he rarely spoke to Zhan Yao these days. His father tried to give him news of Zhan Yao, but he changed the subject. If that damn Cat couldn’t make the effort, then screw him.

He solved a lot more murders. The old medical examiner retired and Gongsun started working with him. He met Ma Han and Wang Shao and Zhao Fu. 

Then one day he screeched up to a crime scene and found an intruder examining the surroundings. An intruder in a dark coat with a supercilious look. What the hell was Zhan Yao doing here?

They fought, but in the end, Bai Yutong had to work with him if he wanted SCI. And he _really_ wanted to be in charge of SCI. 

After a few cases, he decided it wasn’t as bad as he’d expected. Zhan Yao was still a damned genius, even if he was irritating, and it was good to have someone that smart on their side if they were up against a genius like Zhao Jue.

It felt like they were winning until the two of them narrowly escaped death on an exploding boat and subsequent near-drowning. Dragging an unconscious Zhan Yao up the beach, Yutong was incandescently angry. “Don’t you dare die. Don’t you dare. I’m not done yelling at you yet.”

Zhan Yao’s first choking breath felt like Yutong could start breathing as well. “Don’t do that to me again,” Yutong said, almost falling over in relief.

“Stop sounding like you care or I might misunderstand you.” Zhan Yao choked up some more water, distracting Yutong from his words.

“I just don’t want to have to explain to our families that I let you drown.”

“Of course.” Zhan Yao almost smiled as Yutong dragged him to his feet. “Let’s go home.”

Their team found them soon, bundling them onto the boat and yanking off wet clothing to wrap them in blankets. Ma Han turned her back and Yutong rolled his eyes as he made sure someone was keeping Zhan Yao from doing something ridiculous like falling into the water again.

As Zhan Yao’s sopping wet shirt was almost ripped off him, Yutong caught a glimpse of his arm and that ridiculous heart that Qingtang had been so obsessed with when they were younger. He very deliberately didn’t look at his own arm, wrapping the warm blankets around his torso and trying to stop shivering.

* * *

Things got better and then they got worse. His working relationship with Zhan Yao improved…but Zhao Jue had survived the explosion as well. And Zhan Yao was too damn fascinated in the man’s work to have the slightest sense of self-preservation.

Not only was he trying to sneak out and meet up with the man alone, he was starting to emulate the man’s techniques and lack of regard for other people’s rights to their own brains.

Every time they encountered the smallest problem, Zhan Yao was ready to solve it by hypnotizing people. The bouncer at the club, a witness, it didn’t matter.

Yutong brought out the big guns and told Zhan Yao outright that he was behaving like Zhao Jue…but it didn’t help.

Chief Bao saw it happening too. Yutong could see it in his eyes when he looked at the two of them, but he seemed equally helpless to stop it.

Zhan Yao was turning into someone else right in front of them and there was nothing they could do. He wouldn’t listen.

Yutong punched the bag in his office even harder, trying to work out his frustrations.

Another mysterious case appeared and they worked long hours. Chief Bao sent everyone home when he walked in to find almost everyone asleep at their desks. Yutong didn’t even have the energy to argue, following Zhan Yao out the door and back to the apartment they still shared. (If he left Zhan Yao alone, he was going to get himself killed immediately. Everyone knew that.)

Collapsing on the couch, Zhan Yao waved at Yutong to shower first and Yutong just nodded. He staggered into the bathroom, stripping his clothing off and barely managing to get it into a pile. Leaning on the counter, he stared at his haggard face and scowled at himself. He turned, about to get in the shower, when he caught a glimpse of his arm.

It looked much like it always had, except there was no familiar heart shape in an awkward location. It was gone.

Yutong stared at his reflection. It didn’t mean anything. Obviously not. They weren’t soulmates for fuck’s sake and he’d probably outgrown the stupid mole or whatever it was years ago. He just hadn’t noticed because Qingtang had annoyed him so much.

Surely that was it. It didn’t mean there was anything seriously wrong.

A traitorous part of his brain reminded him that as of a few months ago, Zhan Yao’s arm had still had that mark. He’d seen it. He’d seen it on him before things went wrong. Before Zhan Yao went wrong.

It was irrelevant. Yutong turned away from the mirror and got in the shower.

* * *

“That’s it!” Yutong exploded a week later after Zhan Yao hypnotized yet another witness just to save them some time.

Zhan Yao paused halfway into getting in the car, brow furrowed as he looked at him. “Hmm?”

“We’re going home.”

“But we—” 

“Shut up.”

Zhan Yao gave him an odd look, then pointedly stared out the window.

Yutong concentrated fiercely on the traffic in order to avoid thinking of anything else, taking turns at a speed that had Zhan Yao muttering under his breath. It was fortunate that most of the traffic cops knew him by now or they’d have been stopped a half dozen times.

Slamming into a parking space, Yutong was out of the car before Zhan Yao had even unbuckled his seatbelt. Arms crossed, Yutong waited as Zhan Yao leisurely exited the vehicle and meandered past him, raising an eyebrow.

Yutong waved at the apartment door and followed Zhan Yao in, closing the door behind them with a slam.

“Now…what’s this about?” Zhan Yao asked, turning to look at him.

“Take off your jacket.”

Zhan Yao blinked. “What?”

“Take off your jacket. And your shirt.”

With a smirk, Zhan Yao started to slip off his jacket. “I don’t usually strip on the first date, but...”

Yutong didn’t crack a smile.

Zhan Yao tossed his jacket onto the couch, looking at Yutong. “Okay, seriously, what’s—”

“Off. Now.”

Zhan Yao’s expression went cold but he swiftly removed his tie and shirt, tossing them after the jacket. Stalking forward, Yutong grabbed his left arm and looked at it. The mark was gone. There was nothing that could even be vaguely interpreted as a heart.

Dropping Zhan Yao’s arm, Yutong took a step back. He was being ridiculous. This was…it couldn’t…

Zhan Yao looked down at his arm, puzzled. It took a moment but his eyes widened. “It’s gone,” he said into the silence, sounding shocked.

Yutong swallowed sharply. 

Slowly, Zhan Yao looked up at him, eyes still wide. “How…”

“People change,” Yutong said. Turning, he started out the door, moving automatically to get away from a situation he didn’t understand and couldn’t control. He stopped when Zhan Yao grabbed his arm. “Don’t.”

“Don’t you dare leave right now,” Zhan Yao said.

Glancing over his shoulder, Yutong glared at him, pulling his arm away. “I don’t want to talk about it.”

“Too bad. You’re the one who introduced the topic.” Zhan Yao gave him a look obviously intended to convey that he shouldn’t try to leave again, then walked over to pick up his shirt and put it back on.

Yutong sniffed in irritation, but stepped away from the door, walking toward the balcony instead to pull the curtains open.

“I thought you didn’t believe any of this bullshit.” Zhan Yao was being deliberately crass and it sounded odd from him.

“I…” Yutong rubbed his face. “I don’t know.”

“Am I your soulmate?”

“Maybe you were.”

Zhan Yao’s intake of breath was almost a gasp. “Damn you.”

Leaning against the glass, Yutong stared out at the cars driving by. 

“Say something.”

“There’s nothing to say.”

Zhan Yao grabbed his arm again, pulling him face-to-face. “Bai Yutong…”

“Oh, are you planning to hypnotize me into talking to you?” Yutong glared at him.

Dropping his arm like a hot potato, Zhan Yao stared in horror. “No!”

“Are you sure?” Yutong stuck his hand in his pocket, jingled his car keys. “I need to go. The team can reach me by phone. I’ll be back at the office in a few hours.”

* * *

He didn’t have a destination. He just needed to be away. So Yutong got in his fancy car and just…drove, cursing at the bad drivers and ridiculous traffic lights, trying not to think about anything in particular.

Eventually he stopped to gas up his car and drove back to the office. Zhan Yao was there and everyone turned to stare when Bai Yutong strode in, but he refused to think about what Zhan Yao might have told them.

“So, what have you lazy bums done while I was gone?”

A chorus of heckling shouts met him, along with a lot of good detective work. Arms crossed, he leaned against a desk and listened, doing his best to ignore Zhan Yao.

He barked out orders and strode toward his office. Zhan Yao followed him in. Turning, Yutong waited.

“Mouse…”

“Cat.”

“I wouldn’t. I wouldn’t ever do that to you.”

Yutong pondered that. “Good to know you have limits.” Then he sat down at his desk and flipped open a file. He knew that Zhan Yao knew it was a random file and had nothing to do with the current case, but Zhan Yao took the hint and left.

Flipping closed the irrelevant file, Yutong leaned back in his chair and went through the current case in his head again, looking for threads they’d failed to follow.

* * *

They solved the case, of course. And the one that followed. Yutong cooked for Zhan Yao just as he always had. They worked together like normal colleagues, but just like normal colleagues. Yutong allowed no personal conversations.

Qingtang tried to talk to him, but Yutong just stared at her until she gave up and went away. When Gongsun entered his office, Yutong took one look at his face and kicked him out. Most of the rest of the team knew things were bad and were tiptoeing around, but Yutong didn’t care.

At his desk, determinedly not staring at the wall that separated him from Zhan Yao, Yutong looked up at a very tentative knock on his door. “Come in,” he barked.

It was obvious who was behind the door when it creaked and inched its way open. “Get in here, Bai Chi,” he said. “I don’t bite.”

“Yes, you do, sir.”

That almost made him smile. The kid was definitely less of a coward than when he’d started. They’d toughen him up eventually. “Fair point. What is it?”

Bai Chi stood in front of his desk, hands clasped. “Um, sir…it’s about Dr. Zhan.”

Yutong had honestly not expected it to come from Bai Chi, so he was unprepared.

“Everyone is unhappy when you fight and he looks really sad,” Bai Chi said very quickly.

“Get out,” Yutong snarled.

“I’m sorry, sir.” Bai Chi bowed his way out.

Yutong barely restrained himself from throwing something at the door after he was gone. Damned people interfering where it wasn’t their business.

* * *

The bearded man, well, the multiple bearded men appeared. Children were in danger and Zhan Yao dared Yutong’s wrath to ask to bring in Zhao Jue to help.

Staring at each other over Zhan Yao’s mobile, Yutong was at a loss. Could he trust Zhan Yao’s judgment? He always had before, even when the man irritated him.

Gritting his teeth, Yutong thought that he wasn’t going to let his decisions be made by a damned superstition. “Bring him in,” he said.

His nerves were on edge the entire time, especially leaving the two of them alone in the interrogation room with Jiejie. That man could be doing anything and there was no way to know. Bai Chi was watching him worriedly on the other side of the corridor but Yutong had no attention to spare to help him.

The plan worked and they followed the villains to the abandoned housing complex, where they rescued the children…and lost the villains. Yutong wanted to curse and yell, but he held his temper in and took Zhan Yao into the woods with him to find the people responsible.

Even to someone trained in combat, it all seemed to happen impossibly fast.

Luo Tian was down and possibly out, while Zhan Yao held a gun to Du She’s head. “You’re not actually going to kill him?” Yutong asked, incredulous.

So focused on concern for Zhan Yao, Yutong missed the chance to stop Du She from grabbed Zhan Yao and using him as a shield, hand around his neck.

Damn Zhan Yao, telling him to take the others and run from the explosives, as if Yutong could ever leave him behind.

Once again, Luo Tian saved them, saved Zhan Yao and returned him to Yutong. The explosions sent them all flying, but they were in one piece. But Leonard was dead, Du She had blown himself up, and Zhao Jue was who-knew-where, undoubtedly starting on a new plan.

When it was all over, they stood in the almost empty space of Zhao Jue’s gallery, Zhan Yao staring at the painting of a demon and an angel, oddly Christian iconography for this moment.

“When you were holding the gun on Du She. Would you have killed him?” Yutong asked eventually.

“If I felt there was no other choice. I couldn’t let him hurt more people. I really don’t want anything to happen to you.” Zhan Yao paused. “Do you blame me?”

Yutong took a deep breath and considered the words that had been bouncing around his head for the last 24 hours. Finally, he spoke. “No, I don’t blame you. Because I understand you. I know your character and your temper. I know your attitude and how you conduct yourself in society. I know that you’re still that Zhan Yao.”

Zhan Yao looked at him, then inclined his head in acceptance. “Let’s go home,” he said.

The car ride was silent, filled with an odd tension that Yutong wasn’t interested in examining. They entered the apartment and took off their shoes in the same silence. 

After discarding his jacket, Zhan Yao dropped onto the couch, leaning on his knees. Yutong waited and finally Zhan Yao lifted his head and spoke. “Have you looked at your arm?”

“No.” Yutong glared at him. “And if you take off your shirt, the last thing I’m going to be doing is inspecting your arm.”

Zhan Yao’s lips twitched. “Sounds good to me.” He started to unbutton his shirt.

With a growl, Yutong pushed him against the back of the couch and took over the job. Whatever the hell was going on, he was claiming Zhan Yao as his. Everything else could wait.

—end—

**Author's Note:**

> The author humbly wonders if Zhao Jue was deliberately trying to break the bond between them because he doesn’t want Zhan Yao to have any attachments. However, there was no way to fit that into this story as conceived without writing an additional 10,000 words, so it is left as an exercise for the reader.


End file.
